diff --git a/fsl/utils/fslsub.py b/fsl/utils/fslsub.py
index 5957ba6f387d6e46190407e01b733f81fcd025c9..a770cc623ad3cb880ed458ba679b9e84c1b4e5da 100644
--- a/fsl/utils/fslsub.py
+++ b/fsl/utils/fslsub.py
@@ -225,6 +225,8 @@ def _flatten_job_ids(job_ids):
         """Unpack the (nested) job-ids in a single set"""
         if isinstance(job_ids, str):
             return {job_ids}
+        elif isinstance(job_ids, int):
+            return {str(job_ids)}
         else:
             res = set()
             for job_id in job_ids:
diff --git a/tests/test_fslsub.py b/tests/test_fslsub.py
index 45b4d9e0eaa8a0eeda55db1172be29f162de9ce6..878e9b32c14d5dbb838290133b3b5ebdf87fcaa6 100644
--- a/tests/test_fslsub.py
+++ b/tests/test_fslsub.py
@@ -9,7 +9,7 @@ from fsl.utils import fslsub
 
 
 def test_flatten_jobids():
-    job_ids = ('12', '27', '35', '41', '721')
+    job_ids = ('12', '27', '35', '41', 721)
     res = '12,27,35,41,721'
 
     assert fslsub._flatten_job_ids(job_ids) == res